1. The Field of the Invention
The present disclosure relates generally to systems for securing a pair of suture lengths together or for using a single strand of suture to secure tissues together in a patient without the need for tying a knot.
2. The Relevant Technology
During intravascular and other related medical procedures, catheters are typically inserted through an incision or puncture in the skin and underlying tissues to access an artery or vein, typically in the groin, neck, or subclavian areas of a patient. The catheter can be inserted through a puncture in the blood vessel and guided to the desired site to perform interventional procedures such as angiography, angioplasty, stent delivery, plaque removal, and infusion of a therapeutic substance.
Often these procedures are performed by inserting a hollow needle through a patient's skin and muscle tissue into the vascular system. A guide wire then is passed through the needle lumen into the patient's blood vessel. The needle is removed and an introducer sheath is advanced over the guide wire into the vessel. The catheter typically is passed through the lumen of the introducer sheath and advanced over the guide wire into position for the medical procedure.
After the procedure is completed and the catheter and introducer sheath are removed from the patient, however, the access hole must be closed to prevent hemorrhage. This is typically achieved by applying pressure over the blood vessel manually and then by applying a pressure bandage or a compressive weight. With conventional methods, the rate of post-puncture hemorrhage is high, which can cause considerable complications. This impediment is exacerbated by the concomitant use of anticoagulant medications such as heparin or warfarin and by anti-platelet drugs, which are commonly used following a procedure in order to prevent clot formation and thrombus and/or to treat vascular disease.
In another common approach, one or more sutures are used to close the access hole. Typically, the surgeon manually ties together a suture pair to close the opening; however, automatic suture tying systems have also been developed.
Although using sutures have been found to be an effective way of closing an opening in tissue, there are a number of disadvantages of knotting sutures together to close the opening. For example, manual knot tying requires considerable dexterity. Also, manual knot tying can take considerable time. Knot tying is further complicated by the fact that surgical sutures have low friction surfaces. Therefore, it is typically necessary for a surgeon to include many “throws” when tying the knot. This multiple-throw problem occurs even if an automatic knot tying device is used. Unfortunately, as the number of loops or “throws” incorporated into the knot increases, the knot becomes increasingly large and bulky.
Moreover, the surgeon typically needs to handle strands of adequate suture length prior to commencing manual knot tying. Thus, manual knot tying requires considerable space both in which to view, and to perform, the actual suture knot tying. Therefore, knot tying is particularly difficult in areas of limited available space or access, such as, for example, at the back of the patient's heart during a coronary artery bypass graft (CABG) operation, or at the artery in the tissue tract after a femoral artery catheterization procedure.
Furthermore, manually tied knots often lock prior to reaching the intended amount of tension to be applied to the tissue, thereby potentially leading to an incomplete closure. This can be particularly important in sealing arterial punctures, which are relatively high pressure systems. For example, under normal blood pressure, the arterial system has a pressure of about 104/80 mmHg or more. Failure to completely close arterial holes can result in hematoma, exsanguination, and other catastrophic consequences, including limb amputation and death.